West Coast Transients (Biggs)

Photo Credit: Gary Sutton

T099 Bella, T099D, and T124A1 Bonapartes (inner coast subpopulation)
Photo Credit: Gary Sutton

West Coast Transients (Biggs)

The West Coast Transients (Biggs) population consists of ~370 individuals. They are silent hunters, often staying underwater for long periods of time with little to no vocalizations. They're also not as surface active as the resident ecotypes, with very little breaching, splashing, or other disruptive behaviors during their hunts. They often celebrate a successful hunt with breaches, tail slaps, spyhops, and other surface-active behavior.

Range map. Red is the Outer Coast Subpopulation range, yellow is the Inner Coast Subpopulation range, and red-yellow stripes are where the subpopulations overlap.

Figure from McInnes et al., 2025 (https://doi.org/10.1371/journal.pone.0325156)

Species: Orcinus orca rectipinnus

Population Numbers:
Transients, like other populations, are matrilineal, but matrilines often break away into groups of 4-6 to keep up stealth. Due to the prey they hunt, they rarely vocalize to avoid detection by their prey. There are ~370 transients in this population.

Population Status: Threatened (CAN- whole population)

Study Years: 1976-present (whole population)

Range: Central California to Southeast Alaska

Diet: Marine Mammals- 64% harbor seal, 9% Steller sea lions, 3% California sea lions, <0.005% northern elephant seal (only one observation), 21% harbor porpoise, <5% Dall's porpoise, minke whales, and gray whale calves

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